The invention relates generally to floor gratings, particularly those utilized in the entrances to buildings and the like. Typically, the gratings comprise rigid tread rails typically formed of metal arranged in a side by side series, with a narrow space between the rails to allow for the passage of water, slush and dirt. The rails are rigidly secured and are recessed in the floor surface, so as to form a substantial continuation of the floor surface. In the recess area of the floor where the grating is supported there may also be included a drain for removal of excess water, dirt and slush.
It has been customary to construct floor gratings with the structural element extending both transversely and longitudinally. Typically, the grating structure is formed of a plurality of tread-supporting members, arranged in a side by side relation, usually spaced from each other. These elements, which are normally extended transversely, are rigidly joined by a plurality of longitudinally extending locking bars which secure the assembly of tread supports in the desired spaced relation and with a desired degree of rigidity.
Floor grating assemblies are well known in the art. The Berndt U.S. Pat. No. 4,903,444, Bustin U.S. Pat. No. 4,027,451, Viehmann et al. U.S. Pat. No. 3,383,822 and the Reifsnyder U.S. Pat. No. 4,112,640 are representative of known floor grating structures. The latter two references illustrate common techniques of construction wherein the tread rails are aligned with openings for the reception of a plurality of spacing bars arranged to extend transversely from one side of the assembly to the other. The spacing bars are inserted into tread rail openings in a predetermined rotational orientation and rotated into a locking position so that the tread rails are in a desired spaced relation.
Among the disadvantages of the known constructions of grating structures is the comparative difficulty of assembly. The necessity of first aligning and spacing structural elements or tread supports in order to receive connecting elements arranged at right angles thereto would necessitate an elaborate assembly procedure.
The present invention is directed to improvements in the construction of floor grating structures. The structure of the present invention provides for improved and simplified spacing bar arrangement which supplies adequate support and facile construction.